Life Processes PYQ Class 10

1

Secretion of less saliva in mouth will effect the conversion of:

[1 marks]

A. proteins into amino acids B. fats into fatty acids and glycerol C. starch into simple sugars D. sugars into alcohol

2

The breakdown of glucose has taken the following pathway:

Glucose $\xrightarrow{(a)}$ Pyruvate + Energy $\xrightarrow{(b)}$ Lactic acid + Energy

The sites 'a' and 'b' respectively are :

[1 marks]

A. Mitochondria and Oxygen deficient muscle cells B. Cytoplasm and Oxygen rich muscle cells C. Cytoplasm and Yeast cells D. Cytoplasm and Oxygen deficient muscle cells

3

(a)

Besides minimising the loss of blood, why is it essential to plug any leak in a blood vessel ? Name the component of blood which helps in this process and state how this component perform this function.

OR

(b)

(i)	The transport system in plants is relatively slower than in animals. Give reasons.
(ii)	State the role of phloem in the transport of materials in plants.

[2 marks]

4

The maintenance functions of all living organisms must go on even when they are not doing anything particular. Even when we are just sitting in a class or even asleep, this maintenance job has to go on. These maintenance processes require energy to prevent damage and break-down of cells and tissues, which is obtained by the individual organism from the food prepared by the autotrophs, called producers

(a)	Name and define the process by which green plants prepare food.
(b)	Write chemical equation involved in the above process.
(c)	(i) A mild non-corrosive basic salt ‘A’, used for faster cooking, is strongly heated to produce a compound ‘B’, that is used for removing permanent hardness of water. Identify A and B and also write the equation for the reaction that occurs when A is heated.
	OR
(c)	(ii) Define water of crystallisation. Give two examples of salts that have water of crystallisation.

[4 marks]

5

A stomata closes when :

(i) it needs carbon dioxide for photosynthesis.

(ii) it does not need carbon dioxide for photosynthesis.

(iii) water flows out of the guard cells.

(iv) water flows into the guard cells.

The correct reason(s) in this process is/are :

[1 marks]

A. (i) only B. (i) and (iii) C. (ii) and (iii) D. (ii) and (iv)

6

Assertion (A): The rate of breathing in aquatic organisms is much faster than in terrestrial organisms.

Reason (R): The amount of oxygen dissolved in water is very high as compared to the amount of oxygen in air.

[1 marks]

A. Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A). B. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A). C. Assertion (A) is true, but Reason (R) is false. D. Assertion (A) is false, but Reason (R) is true.

7

State one role of each of the following in human digestive system :

(i) Hydrochloric acid

(ii) Villi

(iii) Anal Sphincter

(iv) Lipase

[2 marks]

8

(i) Why is respiratory pigment needed in multicellular organisms with large body size ?

(ii) Give reasons for the following:

1. Rings of cartilage are present in the throat.
2. Lungs always contain a residual volume of air.
3. The diaphragm flattens and ribs are lifted up when we breathe in.
4. Walls of alveoli contain an extensive network of blood vessels.

[3 marks]

9

An organism which breaks down the food material outside the body and then absorbs it is

[1 mark]

A. a plant parasite, Cuscuta B. an animal parasite, Tapeworm C. a bacteria, Rhizobium D. a fungi, Rhizopus

10

Consider the following statements about small intestine and select the one which is NOT correct:

[1 mark]

A. The length of the small intestine in animals differs as it depends on the type of food they eat. B. The small intestine is the site of complete digestion of food. C. The small intestine receives secretions from liver and pancreas. D. The villi of the small intestine absorb water from the unabsorbed food before it gets removed from the body via the anus.

11

Assertion (A): Blood clotting prevents excessive loss of blood.

Reason (R): Blood clotting is due to blood plasma and white blood cells present in the blood.

[1 mark]

A. Both (A) and (R) are true and (R) is the correct explanation of (A). B. Both (A) and (R) are true, but (R) is not the correct explanation of (A). C. (A) is true, but (R) is false. D. (A) is false, but (R) is true.

12

(a) Name the type of blood (oxygenated / deoxygenated) transported by each of the following mentioning the path (i.e. from one organ (which place) to another (which place)).

(i) Vena cava

(ii) Pulmonary artery

OR

(b) With the help of a schematic flow chart, show the breakdown of glucose in a cell to provide energy

(i) in the presence of oxygen

(ii) in lack of oxygen

[2 marks]

13

Name the part of the human excretory system where nephrons are found. Write the structure and function of nephrons.

[2 marks]

14

(a) (i) State the role of ATP in cellular respiration.

(ii) What ensures sufficient exchange of gases in plants?

(iii) State the conditions on which the direction of diffusion of gases in plant depend upon.

OR

(b) (i) What is the internal energy reserve in plants and animals?

(ii) How desert plants perform photosynthesis if their stomata remain closed during the day?

[3 marks]

Life Processes PYQ Class 10

Sign in to continue